ok, we are talking about two totally different things here. I am talking about driving down cost of manufacturing. As you see more and more white box sales, it becomes cheaper and cheaper to manufacture various components. So if Google sells a Nexus at cost right now for $200... soon they can sell at cost for $175 then $150...

White box manufacturing helps drive down the cost of MAKING the tablets... while also creating pressure to sell at low prices. Yes, the Nexus isn't going to drop in price unless the manufacturing cost drops.. which is exactly what increased white box production does. Along the way, it helps make sure some idiot company like Motorola thinks twice before releasing a $600 tablet again.

What are they driving down the costs of though? Give me an example?

I just don't think your premise makes sense. You have a handful of processors that can run modern day tablets. The S4, Tegra 3, OMAP whatever. And you have a limited supply there. Also with your screens.

With desktops and laqptops it was different, because you had a giant, open ecosystem. With phones and tablets, it's completely closed. Apple is proprietary, Microsoft is almost there, and Google supports one or maybe two each cycle, and leaves it up to the manufacturers to make it work. And you still have plenty of proprietary parts in there they have to make work. There's no "driver" system. There's no real economy of scale, outside of perhaps Apple and Samsung. And between those two, neither wants to drive down prices.